Liquid medicine is especially vulnerable to freezing or high heat. One reader wrote that a delivery of insulin was left on a porch for hours. She checked with the mail-order pharmacy, which told her that the drug was probably fine. Despite the reassurance, she could not get her blood sugar under control for two months. She became lethargic and confused until the doctor gave her an injection of insulin in the office. Her medication seems to have been affected by the exposure.

Q: Doctors believe Ambien is a relatively benign sleeping pill, but it wreaked havoc with my stomach. The bloating was the worst, followed closely by the acid reflux and extreme eructation (burping beyond belief).

It has been three years since I quit Ambien. I felt better almost immediately.

To sleep, I use melatonin, a regular 15-minute cool-down yoga routine and a cup of herbal tea before bedtime. I also have learned to quiet my mind if I start worrying that I will not get to sleep by reassuring myself that I WILL sleep eventually.

A: Thank you for sharing your experience. More than 100 visitors to our website have reported similar problems. Research reveals a connection between the use of zolpidem (Ambien) and reflux-related GI damage (Clinical Gastroenterology and Hepatology, September 2009).

Your nondrug approaches to insomnia sound sensible. A cup of fennel tea might be useful against both sleeplessness and indigestion.

Q: Are others concerned like I am when a barista touches the top of my coffee cup? When this happened recently, I complained and walked away in frustration. I’m not trying to be difficult, but I don’t want anyone else’s cold, flu or whatever.

A: We share your concern. In some cases, the same person who takes your money fills the coffee cup and then seals the lid. One reader offered the following solution: “When a server at any restaurant handles my food and my money, I ask him to please put on gloves and then handle my food — the reordered food, that is.”

In their column, Joe and Teresa Graedon answer letters from readers. Write to them c/o King Features Syndicate, 300 W. 57th St., 15th floor, New York, NY 10019, or via their website:www.peoplespharmacy.org